When you register with an organization, you will receive the following email below from ePACT.

Click the orange  Complete Request  at the bottom of the email to get started.

Invitation Email Preview:

PLEASE NOTE: You MUST create an ePACT account after registration. If you did not perform this step you will NOT be able to login to complete the form, regardless of how many times you reset your password. Accounts are NOT automatically created and need to manually be created by you AFTER you have accepted the invite.

You will then be prompted to answer a series of questions. Make sure you see green checkmarks all the way through on the left hand pane as this indicates you have answered all prompted questions successfully. 
Anything indicated with a red (*) caution sign needs to be looked over.

 Please be sure to click on the BLUE "Share with the Organization" button in the final step to complete the process.